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Recently Updated NPI Information — some details in this NPI profile have been updated in the NPI registry within the last 60 days.

AARON THOMAS BYCZYNSKI
NPI 1457054942
Internal Medicine in Milwaukee, WI

Active since March 23, 2023PECOS Enrolled
945 N 12TH ST, MILWAUKEE, WI 53233(414) 219-2000 Get Directions Write a Review

NPPES record last updated: July 24, 2026. Verified against the NPPES registry weekly; last sync: August 09, 2026.

Record update history: Jul 24, 2026, Mar 23, 2023 (2 updates tracked since 2023).

About Aaron Thomas Byczynski NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

AARON THOMAS BYCZYNSKI (NPI 1457054942) is an individual internal medicine provider in Milwaukee, Wisconsin, licensed in Wisconsin (81699) and active in the NPI registry since March 2023. He is enrolled in Medicare PECOS, maintains a secondary practice location in Milwaukee, and is a graduate of West Virginia School Of Osteopathic Medicine (2023).

NPPES Registry Identity

NPI1457054942
Entity TypeIndividualMale
Primary Taxonomy207R00000X
Provider Legal NameAARON THOMAS BYCZYNSKI
Location Address945 N 12TH STMilwaukee, WI 53233-1305
Mailing AddressPo Box 735044Chicago, IL 60673-5044 · (800) 326-2250
Phone(414) 219-2000
Sole ProprietorNo
Medical School CMSWest Virginia School Of Osteopathic MedicineGraduated 2023
Enumeration DateMarch 23, 2023
Last NPPES UpdateJuly 24, 20262 updates tracked since enumeration
NPPES CertifiedJuly 24, 2026
✔ NPI 1457054942 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207R00000X
License✔ Licensed in WI · 81699
Definition
A physician who provides long-term, comprehensive care in the office and the hospital, managing both common and complex illness of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer, infections and diseases affecting the heart, blood, kidneys, joints and digestive, respiratory and vascular systems. They are also trained in the essentials of primary care internal medicine, which incorporates an understanding of disease prevention, wellness, substance abuse, mental health and effective treatment of common problems of the eyes, ears, skin, nervous system and reproductive organs.
945 N 12TH ST, Milwaukee, WI 53233
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Secondary Practice Location 1

Location 18701 Watertown Plank RdMilwaukee, WI 53226-3548 · Phone (414) 955-4575

Other Identifiers 1

Medicaid100257950WI

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Aaron Thomas Byczynski is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

PECOS PAC ID8820451198
PECOS Enrollment IDI20260505000150
Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 53233 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$123.69 typical visit price
range $53.90 – $163.24
Typical copayment $30.92 (range $13.47 – $40.81)
Most-billed visit code 99204
Established Patient
$95.41 typical visit price
range $17.40 – $133.76
Typical copayment $23.85 (range $4.35 – $33.44)
Most-billed visit code 99214
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Other Providers at the Same Location NPPES 20

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

RICHARD COMPTON KURTZ II MD
Family Medicine
945 N 12TH ST
MILWAUKEE, WI 53233
Milwaukee County (414) 219-0000
MS. ANN M YOCKEY APNP
Nurse Practitioner
945 N 12TH ST
MILWAUKEE, WI 53233
Milwaukee County (414) 219-5800
SARAH E KRAEMER PA-C
Physician Assistant
945 N 12TH ST
MILWAUKEE, WI 53233
Milwaukee County (414) 219-6777
DR. ALINA M WINANS MD
Emergency Medicine
945 N 12TH ST
MILWAUKEE, WI 53233
Milwaukee County (414) 219-2000
MS. MORANDA MARIA MEDINA-LOPEZ RN
Registered Nurse
945 N 12TH ST
MILWAUKEE, WI 53233
Milwaukee County (414) 219-2000
XENAYSHMA ZHAYLEENE GNAS-PACHECO
Registered Nurse (Registered Nurse First Assistant)
945 N 12TH ST
MILWAUKEE, WI 53233
Milwaukee County (414) 000-0000
PROGRESSIVE COMMUNITY HEALTH CENTERS, INC.
Clinic/Center (Federally Qualified Health Center (FQHC))
945 N 12TH ST, URGENT CARE
MILWAUKEE, WI 53233
Milwaukee County (414) 935-8000
JOSEPH SHAOUL
Anesthesiologist Assistant
945 N 12TH ST
MILWAUKEE, WI 53233
Milwaukee County (414) 219-2000

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Aaron Byczynski's NPI number?

The NPI number for Aaron Byczynski is 1457054942. It was assigned to this individual provider in the NPPES registry on March 23, 2023.

Where is Aaron Byczynski located?

Aaron Byczynski practices at 945 N 12th St, Milwaukee, WI 53233. The listed phone number is (414) 219-2000.

What is Aaron Byczynski's specialty?

The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.

Is Aaron Byczynski enrolled in Medicare?

Yes. Aaron Byczynski is registered in the Medicare PECOS enrollment system.

When was this NPI record last updated?

The NPPES record for Aaron Byczynski was last updated on July 24, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 18 days ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.